Typical operating characteristics, Electrical characteristics (continued) – Rainbow Electronics MAX8903A User Manual

Page 5

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MAX8903A

2A 1-Cell Li+ DC-DC Charger for USB*

and Adapter Power

_______________________________________________________________________________________

5

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Sinking 1mA

8

50

Logic Output Voltage, Low
(CHG, FLT, DOK, UOK)

Sinking 10mA

80

mV

T

A

= +25°C

0.001

1

Open-Drain Output Leakage
C ur rent, Hi g h (CHG , FLT, DOK, UOK)

V

OUT

= 5.5V

T

A

= +85°C

0.01

µA

VL Output Voltage

V

DC

= V

USB

= 6V, I

VL

= 0 to 1mA

4.6

5

5.4

V

VL UVLO Threshold

V

VL

falling; 200mV hysteresis

3.2

V

Thermal Shutdown Temperature

160

°C

Thermal Shutdown Hysteresis

15

°C

ELECTRICAL CHARACTERISTICS (continued)

(V

DC

= V

USB

= 5V, V

BAT

= 4V, circuit of Figure 2, T

A

= -40°C to +85°C, unless otherwise noted. Typical values are at T

A

= +25°C.)

(Note 1)

Note 1: Limits are 100% production tested at T

A

= +25°C. Limits over the operating temperature range are guaranteed by design.

Note 2: For the 100mA USB mode using the DC input, the step-down regulator is turned off and a low-dropout linear regulator is

connected from DC to SYS.

Note 3: For the 500mA USB mode, the actual current drawn from USB is less than the output current due to the input/output current

ratio of the DC-DC converter.

Note 4: For short-circuit protection, SYS sources 25mA below V

SYS

= 400mV, and 50mA for V

SYS

between 400mV and 2V.

Typical Operating Characteristics

(T

A

= +25°C, unless otherwise noted.)

0

20

10

40

30

60

50

70

90

80

100

1.0

2.0

2.5

1.5

3.0

3.5

4.0

4.5

5.0

BATTERY CHARGER EFFICIENCY

vs. BATTERY VOLTAGE

MAX8903A toc01

BATTERY VOLTAGE (V)

EFFICIENCY (%)

V

DC

= 12V

I

BATT

= 0.15A

V

DC

= 8V

V

DC

= 5V

I

BATT

= 1.5A

I

BATT

= 1.5A

0.0

0.5

1.0

1.5

2.0

2.5

3.0

4.0

3.5

4.5

4

8

6

10

12

14

16

SWITCHING FREQUENCY

vs. V

DC

MAX8903A toc02

DC VOLTAGE (V)

SWITCHING FREQUENCY (MHz)

V

BAT

= 3V

R

ISET

= 1.2k

Ω

CEN = 0V

V

BAT

= 4V

SYS EFFICIENCY vs. DC VOLTAGE

MAX8903A toc03

SYS OUTPUT CURRENT (mA)

SYS EFFICIENCY (%)

1000

100

10

10

20

30

40

50

60

70

80

90

100

0

1

10,000

V

DC

= 16V

V

DC

= 11V

V

DC

= 6V

V

DC

= 4.5V

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